Profiler for installation of foundation screw anchors

ABSTRACT

A profiler for use in the installation of a screw anchor for connecting to foundations and the like. The profiler provides a readout of torque being applied by a hydraulic motor which rotates the drill head and screw anchor. The profiler further provides a range sensor which indicates the distance traveled by the drill head and, hence, the distance traveled by the screw anchor into the ground formation. An orientation sensor for the screw anchor may conveniently also be used in the operation of the profiler.

INTRODUCTION

This invention relates to a profiler and, more particularly to a profiler used to provide real-time information concerning the installation of foundation screw anchors.

BACKGROUND OF THE INVENTION

Screw type foundation piles, piers and anchors are conventionally used in construction projects to remedy failing foundations in existing structures as well as to provide foundation support for new construction. There are advantages to screw type foundation piles over more traditional type foundation support methods such as caissons and pile driven supports.

In the installation of screw type foundation piles, it is advantageous to obtain a real time display of torque being applied to the screw type foundation and, in addition, to obtain such torque indication and the depth profile of the screw anchor being installed.

SUMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a profiler for installation of foundation supports such as screw anchors and screw piers, said profiler comprising a first sensor to measure inlet pressure to a hydraulic motor used to rotate said screw anchor, a second sensor to measure outlet pressure from said hydraulic motor, said first and second sensors being utilized to determine torque being applied to said screw anchor by said hydraulic motor, a third sensor to measure the distance traveled by said screw anchor in an earth formation and means for comparing said distance traveled by said screw anchor with said torque applied to said screw anchor over said distance.

According to a further aspect of the invention, there is provided a method of installing a screw anchor comprising applying a torque to said screw anchor by a motor connected to a drill head, allowing said screw anchor to move into a ground formation under the influence of said torque, determining the value of said torque applied to said screw anchor while said screw anchor moves into said ground formation and comparing the torque applied to said screw anchor with the distance traveled by said screw anchor in said ground formation.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Specific embodiments of the invention will now be described, by way of example only, with the use of drawings, in which:

FIG. 1 is a diagrammatic side view of the helical drill or screw anchor being installed into a ground formation by an operator in a typical application while using the profiler according to the invention;

FIG. 2 is a diagrammatic schematic of the control system which provides torque indication of the torque applied to the screw anchor by the hydraulic motor;

FIG. 3 is a diagrammatic and enlarged view of the profiler hardware which is attached to the drill head applying torque to the screw anchor;

FIG. 4 is a side diagrammatic and enlarged view of the drilling equipment with attached screw anchors;

FIG. 5 is a graphical representation of the torque, measured distance and net depth reached by the screw anchor; and

FIG. 6 is a block diagram of the profiler system including the controller and sensors of the profiler.

DESCRIPTION OF SPECIFIC EMBODIMENT

Referring now to the drawings, a profiler used for the installation of a foundation support is generally illustrated at 100 in FIG. 1. It is installed on a tractor 101 which has a boom 102 connected thereto which boom 102 is extended outwardly or inwardly by an operator 103 as the particular job may require. A hydraulic motor 104 (FIG. 4) is connected to the extended end of the boom 102 and may be rotated by the operator 103 through a hydraulic pump 110 which uses a directional control valve 111 to control the direction of rotation of the drill head 134 by controlling the direction of hydraulic fluid flow through the motor 104 by directional control valve 111 which thereby retracts or installs the screw anchor 112.

The profiler 100, seen in enlarged form in FIG. 3, comprises a manifold 113 which is connected to a mounting plate 114. The mounting plate 114 is connected adjacent the hydraulic motor 104 (FIG. 4). An arm 120 is connected to the mounting plate 114 and extends towards the operator 103 as seen in FIG. 1. At the end of the arm 120 remote from the mounting plate 114, a distance sensor 121 is provided to measure the distance of the sensor 121 from the surface of the ground formation 122 into which the screw anchor 112 is installed. The distance sensor 121 may be any one of a number of different known designs, conveniently an optical ranging sensor or an acoustical ranging sensor. As the screw anchor 112 is rotated further into the ground 122 under the influence of hydraulic motor 104, the distance sensor 121 senses the reduced distance and provides this distance information to the operator 103 through direct or indirect readout information such as by way of a PDA or laptop screen 151 (FIG. 6) or by way of an instrument display 150 mounted to be visible to the operator 103.

The profiler 100 further includes a sensor attachment 123 (FIG. 3) which is connected to the mounting plate 114 and the hydraulic manifold 113. The sensor attachment 123 includes two pressure sensors 130, 131, pressure sensor 130 being used to measure the inlet hydraulic pressure to the hydraulic motor 104 (FIGS. 1, 2 and 4) and pressure sensor 131 being used to measure the outlet hydraulic pressure from the hydraulic motor 104. The differential pressure between the inlet and outlet sensors 130, 131, is thereby obtained and by extrapolating this information with known torque values for the particular hydraulic motor 104, a value for the torque being applied to the screw anchor 112 by the hydraulic motor 104 may be obtained.

A tilt sensor 132 (FIG. 3) is likewise conveniently included within the sensor attachment 123. The tilt sensor 132 may be either a one or two axis tilt sensor. It provides the operator 103 with an indication of the orientation of the screw anchor 112 while the screw anchor 112 is being installed or rotated within the ground formation 122.

A controller (FIG. 6) in the form of an embedded microprocessor controller 133 is provided which receives the real time information from the various sensors, namely pressure sensors 130, 131, distance or range sensor 121, and tilt or inclinometer sensor 132 and converts the information to read out information which the operator 103 may view by way of instrument display 150, laptop or PDA screen 151, to assist the installation of the screw anchor 112.

Operation

In operation, the screw anchor 112 intended to be installed into the ground formation 122 will be connected to a drill head 134 through a shear pin release assembly 125 which is connected to drill head 134 which is rotated by hydraulic motor 104 (FIG. 4). The operator 103 will manipulate the boom 102 (FIG. 1) to position the screw anchor 112 in its desired initial position prior to rotation into the ground formation 122. When that position is reached and with the end of the screw anchor 112 at or near its desired initial drilling position, the operator 103 will view the real time information from orientation sensor 132 and manipulate the boom 102 in order to ensure that the foundation support 112 is in its desired initial orientation, i.e, vertical, for example, in the specific embodiment described. When that position is reached, the operator 103 will initiate rotation of the screw anchor 112 into the ground formation 122 by providing hydraulic pressure to the hydraulic motor 104 from hydraulic pump 110 (FIG. 2).

It is known that the screw anchor 112 will provide sufficient support for a certain foundation 140 (FIG. 1) when the torque applied to the screw anchor 112 during installation reaches a certain value; that is, for a certain application, if the screw anchor 112 is to bear a load of a predetermined weight, say the weight of a typical failed foundation for a medium sized residence, the torque required may be 4000 ft.lbs. which will be reached when, for example, the screw anchor 112 reaches a depth of approximately fifteen (15) feet. The operator 103, therefore, will continue to rotate the screw anchor 112 until the torque indicated on the real time read out display reaches that value at which point the screw anchor 112 will be in its installed position and the foundation 140 may be connected to and raised or lowered relative to the screw anchor 112. One or several screw anchors 112 may be used, there being couplings 135 connecting the successive screw anchors 112 until the desired value for the torque is reached. It typically is the case that as the screw anchor 112 moves deeper into the ground formation 122, the torque necessary to rotate the screw anchor 112 will increase.

As the torque applied by the hydraulic motor 104 increases, the screw anchor 112 will move deeper into the ground formation 122. The distance or range 121 will indicate the real time decrease of distance between the drill head 134 and the ground formation 122. A graphical interface 150 (FIG. 5) which may be conveniently viewed, for example, on an instrument display 150 adjacent the operator 103, will indicate to the operator 103 the distance traveled by the drill head 134 and, therefore, the screw anchor 112. The real time value of the torque being applied to the screw anchor 112 by the hydraulic motor 104 may also be viewed. As the screw anchor 112 moves deeper into the ground formation 122, the torque will necessarily and usually show a rise in value towards the desired “set point” for the screw anchor 112.

When the drill head 134 reaches a position near the surface of the ground and the desired torque value for torque being applied to the screw anchor 112 has not yet been reached, the drill head 134 and shear pin coupling 125 will be disconnected from the screw anchor 112 may be connected to the top of the first screw anchor 112. The operator 103 will then manipulate the boom 102 upwardly to a position wherein the second screw anchor 112 may be rotated downwardly into the earth formation 122, while viewing the real time information from the orientation sensor 132 which ensures the operator is correctly positioning the screw anchor 122 for installation. The range sensor 121 will be reset to its initial setting corresponding to the new initial drilling position. Following the initiation of the operation of the hydraulic motor 104, the installation operation of the screw anchor 112 will proceed in a manner similar to that described.

When the desired value for the torque applied to the hydraulic motor 104 is reached, the operation of the hydraulic motor 104 will be terminated. The attachment of the foundation 140 to the screw anchor 112 will proceed as is known.

Reference is now made to FIG. 5 which illustrates a typical graphical display that might be generated for the use of the operator 103 or for subsequent analysis of the installation procedure of the screw anchor 112 by third parties.

The upper graph “A” illustrates the torque being applied to the screw anchor 112 by the hydraulic motor 104 in real time and as sensed by the torque sensors 130, 131 already described. The center graph “B” indicates the distance measured by the range sensor 121 during the installation of the screw anchor 112. The lower graph “C” indicates the net depth reached by the screw anchor 112 during installation. It will be seen that the torque increases as the measured distance between the drill head 134 and the surface 122 of the ground decreases; that is, as the screw anchor 112 screw sinks deeper into the ground formation. The torque is shown to cease at a certain distance measured “D”. At this point, a second screw anchor 112 is connected to the first screw anchor 112 already drilled into the ground formation 122. The drill head 134 is raised to accommodate the second screw anchor 112 and the torque again commences at “E” and continues to increase until the second screw anchor 112 is sunken fully into the ground formation 122. At this point, the operator 103 determines that the first and second screw anchors 112 must be removed in favor of a different screw anchor 112. Thus, the torque is reversed at “F” and becomes negative. The distance between the drill head 134 and ground surface 122 increases as the second screw anchor 112 is removed from the earth and, subsequently, the first screw anchor 112 is removed. At this point “G”, the net depth will be zero on the ordinate of the lower graph “C”. The new screw anchor 112 is then positioned in place and the operator 103 recommences to drill the new screw anchor 112 into the ground formation 122 at “H” as described earlier. When the set point (SP) is eventually reached for the desired value, as illustrated in the graph “A”, the drilling is completed. The net depth of the screw anchor 112 will be seen in the lower graph of FIG. 5 at “J”.

Many modifications will readily occur to those skilled in the art. For example, while the orientation of the screw anchor 112 is usually vertical and, indeed, is vertical during the drilling operation described, the screw anchor 112 may be installed at any angle that is useful to accomplish the installation. For vertical ground interfaces, the installation of the screw anchor 112 may be horizontal and screwed into the ground formation 122 until the desired value for torque is reached.

Although the motor 104 being utilized conveniently is a hydraulic motor, it will be appreciated that the teachings of the present invention would likewise apply to alternative drive systems such as electric and pneumatic motors.

Many further modifications will readily occur to those skilled in the art to which the invention relates and the particular examples provided herein are illustrative of the invention only and should not be taken as limiting its scope as defined in accordance with the accompanying claims. 

1. Profiler for installation of foundation supports such as screw anchors and screw piers, said profiler comprising a first sensor to measure inlet pressure to a hydraulic motor used to rotate said screw anchor, a second sensor to measure outlet pressure from said hydraulic motor, said first and second sensors being utilized to determine torque being applied to said screw anchor by said hydraulic motor, a third sensor to measure the distance traveled by said screw anchor in an earth formation and means for comparing said distance traveled by said screw anchor with said torque applied to said screw anchor over said distance.
 2. Profiler as in claim 1 and further comprising an orientation sensor for determining the orientation of said foundation support.
 3. Profiler as in claim 1 as in claim 1 wherein said first and second sensors are hydraulic pressure transducers.
 4. Profiler as in claim 2 wherein said orientation sensor is an axis sensor.
 5. Profiler as in claim 4 wherein said axis sensor is a one axis sensor.
 6. Profiler as in claim 4 wherein said axis sensor is a two axis sensor.
 7. Profiler as in claim 1 wherein said distance sensor is an acoustic ranging sensor.
 8. Profiler as in claim 1 wherein said distance sensor is an optical range sensor.
 9. Profiler as in claim 1 wherein said pressure differential correlated with said hydraulic motor determines said torque.
 10. Method of installing a screw anchor comprising applying a torque to said screw anchor by a motor connected to a drill head, allowing said screw anchor to move into a ground formation under the influence of said torque, determining the value of said torque applied to said screw anchor while said screw anchor moves into said ground formation and comparing the torque applied to said screw anchor with the distance traveled by said screw anchor in said ground formation.
 11. Method as in claim 10 wherein said motor is a hydraulic motor.
 12. Method as in claim 11 wherein said motor is an electrical or pneumatic motor.
 13. Method as in claim 11 wherein said torque from said hydraulic motor is determined by pressure sensors.
 14. Method as in claim 10 and further comprising monitoring the orientation of said support with an orientation sensor during said application of said torque.
 15. Method as in claim 10 wherein said comparison is done in real time. 